Legislation and Rules of the Air
Air law questions in this domain test whether you can place a rule in the correct legal source and apply it to a concrete traffic situation. Know the hierarchy: international standards (ICAO Annexes, chiefly Annex 2 for rules of the air) are implemented nationally through a primary aviation act and detailed regulations. Candidates must distinguish standards from recommended practices, understand that national rules may be more restrictive than ICAO, and know that the rules of the air apply to all aircraft within a state's territory and, for aircraft registered there, wherever they fly.
Core concepts to master: right-of-way (converging aircraft of the same category - the one on the right has right of way; head-on - both turn right; overtaking - the overtaken aircraft has right of way), cruising levels and the semicircular rule for magnetic tracks, minimum heights over congested and open areas, lights to display by day and night, and the meaning of priority, emergency and intercept signals. Also know the definitions of "aircraft in flight", "controlled flight" and "visibility" as used in the rules.
Traps: questions that swap "shall" for "should" to convert a standard into a recommendation; head-on encounters where the instinct is to turn left; and altitude questions where the applicant forgets that minimum-height rules are subject to take-off, landing and permission exceptions.
Rule of thumb: when two aircraft of the same category converge, look right - the aircraft that has the other on its right gives way, and the giving-way aircraft should avoid passing ahead of, above or below the other unless well clear.
Worked example: A glider and a powered aircraft converge at the same level; the glider is to the right of the powered aircraft. The powered aircraft gives way, because the same-category rule (right of way to the aircraft on the right) applies to both, and gliders are not automatically privileged over powered aircraft - only certain categories (e.g. balloons, towing operations) have specific priority rules.